RFC 3550 · INTERNET STANDARD · 2003

RTP: A Transport Protocol for Real-Time Applications

Overview

RFC 3550, “RTP: A Transport Protocol for Real-Time Applications”, is an Internet Standard document published in July 2003 by H. Schulzrinne, S. Casner, R. Frederick, V. Jacobson. It obsoletes RFC 1889. It has since been updated by RFC 5506, RFC 5761, RFC 6051, RFC 6222, RFC 7022, RFC 7160, RFC 7164, RFC 8083, RFC 8108, RFC 8860. The canonical text is published by the RFC Editor.

Abstract

This memorandum describes RTP, the real-time transport protocol. RTP provides end-to-end network transport functions suitable for applications transmitting real-time data, such as audio, video or simulation data, over multicast or unicast network services. RTP does not address resource reservation and does not guarantee quality-of- service for real-time services. The data transport is augmented by a control protocol (RTCP) to allow monitoring of the data delivery in a manner scalable to large multicast networks, and to provide minimal control and identification functionality. RTP and RTCP are designed to be independent of the underlying transport and network layers. The protocol supports the use of RTP-level translators and mixers. Most of the text in this memorandum is identical to RFC 1889 which it obsoletes. There are no changes in the packet formats on the wire, only changes to the rules and algorithms governing how the protocol is used. The biggest change is an enhancement to the scalable timer algorithm for calculating when to send RTCP packets in order to minimize transmission in excess of the intended rate when many participants join a session simultaneously. [STANDARDS-TRACK]

Abstract as published in the RFC, via rfc-editor.org.

What “Internet Standard” means

A mature, widely-implemented specification that has completed the full IETF standards process — the highest maturity level on the standards track.

Read this RFC

The canonical text of RFC 3550 is hosted at rfc-editor.org. Available in TXT,PS,PDF,HTML.

Relationships to other RFCs
This RFC obsoletes
RFC 1889
Other RFCs from 2003

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